Injectors for supercritical CO2 applications

Abstract

An apparatus and method for injectors for use in combustion systems employing multiple non-solid or gas streams such as supercritical CO 2 systems. The apparatus and method allow for reactants to be injected into a combustion chamber in such a way that combustion is locally inhibited. Injectors employing an inner and outer tube are designed to minimize mixing between the non-solid gas streams and allow for swirling and stratification of the non-solid or gas streams.

The invention claimed is: 
     
       1. An injector, comprising:
 an outer cylindrical tube comprising an inner diameter and a first end and a second end, wherein said first end is connected to a source of a first non-solid and said second end comprises an annular or circular exit; 
 an inner cylindrical tube positioned within said outer cylindrical tube, wherein said inner cylindrical tube comprises an inner diameter and a first end and a second end wherein said first end is connected to a source of a second non-solid and said second end comprises an annular or circular exit; and wherein said second end of said inner cylindrical tube is positioned relative to said outer cylindrical tube such that said second end of said inner cylindrical tube is located an axial distance away from said second end of said outer cylindrical tube; and 
 wherein said inner diameter of said outer cylindrical tube is configured to swirl said first non-solid and said inner diameter of said second cylindrical tube is configured to swirl said second non-solid such that said first non-solid and said second non-solid remain swirled and stratified into separate layers of flow for each non-solid as they flow through the exits of the inner and outer tubes; and 
 wherein said first non-solid comprises supercritical CO2, water, or a mixture of supercritical CO2 and water. 
 
     
     
       2. An injector, comprising:
 an outer cylindrical tube comprising an inner diameter and a first end and a second end, wherein said first end is connected to a source of a first non-solid and said second end comprises an annular or circular exit; and 
 an inner cylindrical tube positioned within said outer cylindrical tube, wherein said inner cylindrical tube comprises an inner diameter and a first end and a second end wherein said first end is connected to a source of a second non-solid and said second end comprises an annular or circular exit; and wherein said second end of said inner cylindrical tube is positioned relative to said outer cylindrical tube such that said second end of said inner cylindrical tube is located an axial distance away from said second end of said outer cylindrical tube; 
 wherein said inner diameter of said outer cylindrical tube is configured to swirl said first non-solid and said inner diameter of said second cylindrical tube is configured to swirl said second non-solid such that said first non-solid and said second non-solid remain swirled and stratified into separate layers of flow for each non-solid as they flow through the exits of the inner and outer tubes; and 
 wherein said first non-solid comprises supercritical CO2 and said second non-solid comprises CH4. 
 
     
     
       3. The injector of  claim 1 , wherein the injector tubes are configured to swirl the first and second non-solids by tangential entry of the first and second non-solids into the injector tubes, rifling on the inner surface of the inner and outer injector tubes, or helical ribbon inserts within the inner and outer injector tubes. 
     
     
       4. A method of injecting an inert into a combustion chamber comprising at least one injector comprising an outer tube and an inner tube positioned within said outer tube comprising the steps of:
 flowing an inert consisting of an inert into said outer tube of said at least one injector; 
 swirling the inert as it flows through said outer tube; 
 flowing a non-solid into said inner tube of said at least one injector; 
 swirling the non-solid as it flows through said inner tube; 
 injecting the swirled inert and swirled non-solid from said outer and inner tubes into said combustion chamber such that the swirled inert delays the mixing of swirled non-solid in said combustion chamber thereby preventing reactions for some distance beyond the point of injection of said at least one injector. 
 
     
     
       5. The method of  claim 4  wherein said non-solid comprises fuel. 
     
     
       6. The method of  claim 4  wherein said non-solid comprises oxidizer. 
     
     
       7. A method of injecting an inert into a combustion chamber comprising at least one injector comprising an outer tube and an inner tube positioned within said outer tube comprising the steps of:
 flowing the inert into said outer tube of said at least one injector; 
 swirling the inert as it flows through said outer tube; 
 flowing a non-solid into said inner tube of said at least one injector; 
 swirling the non-solid as it flows through said inner tube; and 
 injecting the swirled inert and swirled non-solid from said outer and inner tubes into said combustion chamber such that the swirled inert delays the mixing of swirled non-solid in said combustion chamber thereby preventing reactions for some distance beyond the point of injection of said at least one injector, wherein said inert comprises supercritical CO2 and said non-solid comprises CH4. 
 
     
     
       8. A method of injecting a non-solid into a combustion chamber comprising at least one injector comprising an outer tube and an inner tube positioned within said outer tube comprising the steps of:
 flowing the non-solid into said outer tube of said at least one injector to form an outer stream of the non-solid; 
 swirling the non-solid as its flows through said inner tube; 
 flowing the non-solid into said inner tube of said at least one injector to form an inner stream of the non-solid; and 
 injecting the non-solid from said outer and inner tubes into said combustion chamber such that the inner and outer streams enter into said combustion chamber with enhanced turbulence caused by the inner and outer streams experiencing high shear forces due to either a difference in axial velocity, a difference in swirl velocity or direction, or a combination of these effects, downstream of said at least one injector, wherein said non-solid comprises fuel. 
 
     
     
       9. The method of  claim 8  further comprising swirling the non-solid as its flows through said inner tube. 
     
     
       10. A method of injecting a non-solid into a combustion chamber comprising at least one injector comprising an outer tube and an inner tube positioned within said outer tube comprising the steps of:
 flowing the non-solid into said outer tube of said at least one injector to form an outer stream of the non-solid; 
 flowing the non-solid into said inner tube of said at least one injector to form an inner stream of the non-solid; and 
 injecting the non-solid from said outer and inner tubes into said combustion chamber such that the inner and outer streams enter into said combustion chamber with enhanced turbulence caused by the inner and outer streams experiencing high shear forces due to either a difference in axial velocity, a difference in swirl velocity or direction, or a combination of these effects, downstream of said at least one injector, wherein said non-solid comprises fuel. 
 
     
     
       11. The method of  claim 8  wherein said non-solid comprises oxidizer. 
     
     
       12. A method of injecting a first non-solid and a second non-solid into a combustion chamber comprising at least one injector comprising an outer tube and an inner tube positioned within said outer tube comprising the steps of:
 flowing the first non-solid into said outer tube of said at least one injector; 
 flowing the second non-solid into said inner tube of said at least one injector; 
 injecting the first and second non-solids from said outer and inner tubes into said combustion chamber such that the first and second non-solids remain stratified as they enter said combustion chamber thereby delaying mixing of the second non-solid located in the inner tube until downstream of said at least one injector; and 
 wherein said first non-solid comprises supercritical CO2, water, or a mixture of supercritical CO2 and water. 
 
     
     
       13. A method of injecting a first non-solid and a second non-solid into a combustion chamber comprising at least one injector comprising an outer tube and an inner tube positioned within said outer tube comprising the steps of:
 flowing the first non-solid into said outer tube of said at least one injector; 
 flowing the second non-solid into said inner tube of said at least one injector; and 
 injecting the first and second non-solids from said outer and inner tubes into said combustion chamber such that the first and second non-solids remain stratified as they enter said combustion chamber thereby delaying mixing of the second non-solid located in the inner tube until downstream of said at least one injector, wherein said first non-solid comprises a first fuel and said second non-solid comprises a second fuel different than said first fuel. 
 
     
     
       14. A method of injecting a first non-solid and a second non-solid into a combustion chamber comprising at least one injector comprising an outer tube and an inner tube positioned within said outer tube comprising the steps of:
 flowing the first non-solid into said outer tube of said at least one injector; 
 flowing the second non-solid into said inner tube of said at least one injector; and 
 injecting the first and second non-solids from said outer and inner tubes into said combustion chamber such that the first and second non-solids remain stratified as they enter said combustion chamber thereby delaying mixing of the second non-solid located in the inner tube until downstream of said at least one injector, wherein said first non-solid comprises a first oxidizer and said second non-solid comprises a second oxidizer different than said first oxidizer. 
 
     
     
       15. The method of  claim 12  further comprising swirling the first non-solid as it flows through said outer tube. 
     
     
       16. The method of  claim 12  further comprising swirling the second non-solid as its flows through said inner tube. 
     
     
       17. The method of  claim 15  further comprising swirling the second non-solid as it flows through said inner tube. 
     
     
       18. A method of injecting a first non-solid and a second non-solid into a combustion chamber comprising at least one injector comprising an outer tube and an inner tube positioned within said outer tube comprising the steps of:
 flowing the first non-solid into said outer tube of said at least one injector; 
 flowing the second non-solid into said inner tube of said at least one injector; 
 injecting the first and second non-solids from said outer and inner tubes into said combustion chamber such that the first and second non-solids remain stratified as they enter said combustion chamber thereby delaying mixing of the second non-solid located in the inner tube until downstream of said at least one injector, and 
 swirling the second non-solid as it flows through said inner tube, wherein said first non-solid comprises a first fuel and said second non-solid comprises a second fuel different than said first fuel.